Anti-glare film, method for producing same, and use of same

ABSTRACT

An anti-glare film including a light reflectance of 3.8% or less and a haze of 40% or greater. A 60° gloss of the anti-glare film may be 15% or less. The anti-glare film includes a transparent substrate layer, and an anti-glare layer formed on at least one surface of the transparent substrate layer. The anti-glare layer may be a cured product of a curable composition including one or more types of a polymer component and one or more types of a curable resin precursor component, and in particular, at least two components selected from a polymer component and a curable resin precursor component can be phase separated through liquid phase spinodal decomposition. The anti-glare film has improved anti-reflection properties.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the National Phase of PCT International ApplicationNo. PCT/JP2018/034951, filed on Sep. 21, 2018, which claims priorityunder 35 U.S.C. 119(a) to Patent Application No. 2017-237148, filed inJapan on Dec. 11, 2017, all of which are hereby expressly incorporatedby reference into the present application.

TECHNICAL FIELD

The present invention relates to an anti-glare film that can be used invarious display devices such as a liquid crystal display (LCD) and anorganic electroluminescence (EL) display, a method for producing thesame, and use of the same.

BACKGROUND ART

Anti-glare films are widely used as films that prevent reflection ofoutside scenery on a display screen of an image display device, such asan LCD and an organic EL display, and improve visibility. The anti-glarefilm is formed with recesses and protrusions on the surface and isconfigured to scatter reflected light from outside to achieve anti-glareproperties. However, when the scattering of the light from outside istoo great, the entire display of the image display device may turn whiteor display may turn dull color, leading to a decrease in visibility.Also, the recesses and protrusions in the surface and the pixels of theimage display device interfere with one another causing an unsuitablebrightness distribution which may likely to cause sparkle.

The anti-glare film described in JP 2016-33659 A (Patent Document 1) isdesigned to suppress such a reduction in visibility or generation ofsparkle by the anti-glare film. The anti-glare film includes atransparent support and an anti-glare layer, which is formed on thetransparent support, including a surface formed with recesses andprotrusions. In the anti-glare film, a total haze is from 0.1 to 3%, thesurface haze is from 0.1 to 2%, a ratio R_(SCE)/R_(SCI) is 0.1 or less,where a light reflectance ratio R_(SCI) is measured by the specularcomponent included method and a light reflectance R_(SCE) is measured bythe specular component excluded method, the average value of areas ofpolygons, which are formed in a Voronoi partition of the surface formedwith recesses and protrusions by taking the tops of the protrusions asseeds, is from 50 to 150 μm², and a coefficient of variation of theareas of the polygons is from 40 to 80%.

However, with this anti-glare film, of the color black in the displayimage is focused to be black, and specular reflection tends to beincreased and anti-glare properties are not sufficient. That is, arelated art anti-glare film is oriented to simply reduce light(reflection) from fluorescent lights and suppress glare, and reflectance(glare from light reflected by specular reflection) is not reduced.Also, to improve visibility, the light scattering properties must bedegraded to reduce haze. This inevitably leads to a reduction inanti-glare properties. That is, anti-glare properties and visibility arein a trade-off relationship, and satisfying both properties in acompatible manner is considerably difficult. In particular, in displaydevices with medium-sized screens (e.g. PCs such as notebook type PCs orlaptop type PCs, and desktop type PCs, televisions, and the like), it isdifficult to achieve a balance in properties such as visibility,anti-glare properties including anti-reflection properties, andtransparency, and meet the high demands for each individual property.

CITATION LIST Patent Document

Patent Document 1: JP 2016-33659 A (Claim 1)

SUMMARY OF INVENTION Technical Problem

In light of the above, an object of the present invention is to providean anti-glare film with enhanced anti-reflection properties, a methodfor producing the same, and use of the same.

Another object of the present invention is to provide an anti-glare filmwhich can provide satisfactory image visibility, transparency, andanti-glare properties, a method for producing the same, and use of thesame.

Solution to Problem

As a result of diligent research to achieve the object described above,the present inventors discovered that by adjusting a light reflectanceto 3.8% or less and a haze of an anti-glare film to 40% or greater,anti-reflection properties can be improved, and the present inventionwas realized.

In other words, an anti-glare film of the present invention has a lightreflectance of 3.8% or less and a haze of 40% or greater. The anti-glarefilm may have a 60° gloss of 15% or less. The anti-glare film mayinclude a transparent substrate layer, and an anti-glare layer formed onat least one surface of the transparent substrate layer. The anti-glarelayer is a cured product of a curable composition including one or moretypes of a polymer component and one or more types of a curable resinprecursor component. In the curable composition, at least two componentsselected from the polymer component and the curable resin precursorcomponent may be able to be phase separated through liquid phasespinodal decomposition. The polymer component may include a(meth)acrylic polymer that optionally has a cellulose ester and/or apolymerizable group. The cured resin precursor component may include atleast one type selected from polyfunctional (meth)acrylate, epoxy(meth)acrylate, polyester (meth)acrylate, urethane (meth)acrylate, andsilicone (meth)acrylate. The curable resin precursor component mayinclude a silica nanoparticle and/or a fluorine atom.

The present invention also includes a method for producing theanti-glare film including curing a curable composition by heat or anactive energy ray. The method for producing may further include phaseseparating, through liquid phase spinodal decomposition, at least twocomponents selected from a polymer component and a curable resinprecursor component by applying a curable composition including one ormore types of polymer components and one or more types of curable resinprecursor components on a support and drying. In the curing, a phaseseparated curable composition may be cured by heat or an active energyray.

The present invention also includes a display device including theanti-glare film. The display device may be an organic EL display or aliquid crystal display.

The present invention includes a method of improving anti-glareproperties and visibility of an anti-glare film, including adjustinglight reflectance to 3.8% or less and haze to 40% or greater.

Note that in the present specification and the claims, (meth) acrylateincludes both methacrylic acid esters and acrylic acid esters.

Advantageous Effects of Invention

In the present invention, an anti-glare film of the present inventionhas a light reflectance of 3.8% or less and a haze of 40% or greater,giving the anti-glare film improved anti-reflection properties. In otherwords, in the anti-glare film of the present invention, by reducing thereflectance, the light entering the eyes is reduced and glare issuppressed, and by having high haze, reflections of fluorescent lightand the like are reduced and glare is suppressed, giving the anti-glarefilm improved anti-glare properties. Also, by a specific curablecomposition undergoing liquid phase spinodal decomposition, satisfactorylevels of image visibility, transparency, and anti-glare properties canbe achieved.

DESCRIPTION OF EMBODIMENTS

Optical Properties of Anti-Glare Film

The anti-glare film of the present invention has light reflectance andhaze adjusted within a specific range, and thus anti-glare propertiesincluding anti-reflection properties can be improved. Consequently, theanti-glare film of the present invention is useful as an anti-glare filmof a display device.

The light reflectance of the anti-glare film of the present invention isrequired to be 3.8% or less and from the perspective of anti-reflectionproperties from about 0.5 to 3.7%, preferably from about 1 to 3.6%, morepreferably from about 1.5 to 3.5% (particularly from 2 to 3%), forexample. A light reflectance within such a range is effective in displaydevices with a medium-sized screen and particularly effective in displaydevices with a resolution from about 50 to 150 ppi (laptop type ordesktop type PCs, televisions, and the like). Furthermore, among displaydevices with a medium-sized screen, from the perspective of obtaining abalance between visibility, transparency, and anti-glare properties, adisplay device with a resolution of greater than about 150 ppi and about300 ppi or less (notebook type PC, tablet PC, and the like) has a lightreflectance of from about 2 to 3.8%, preferably from about 3 to 3.78%,and more preferably from about 3.5 to 3.75%, for example. When lightreflectance is too great, reflected light reduces visibility.

Note that in the present specification and claims, light reflectance canbe measured according to JIS Z8701 and specifically by the methoddescribed in Examples below.

The anti-glare film of the present invention has visibility and a highhaze. Specifically, haze is required to be 40% or greater. However, fromthe perspective of enhancing anti-glare properties, the haze may be fromabout 40 to 100%, preferably from about 50 to 99.9% (for example, from80 to 99.5%), and more preferably from about 85 to 99% (particularly,from 90 to 98%), for example. A haze within such a range is effective indisplay devices with a medium-sized screen and particularly effective indisplay devices with a resolution from about 50 to 150 ppi. Furthermore,among display devices with a medium-sized screen, from the perspectiveof obtaining a balance between visibility, transparency, and anti-glareproperties, a display device with a resolution of greater than about 150ppi and about 300 ppi or less has a haze of from about 40 to 70%,preferably from about 42 to 60%, and more preferably from about 43 to50%, for example. When haze is too low, anti-glare properties arereduced. When haze is too high, visibility may be reduced.

The total light transmittance of the anti-glare film of the presentinvention is, for example, 70% or greater (for example, from 70 to100%), preferably from about 80 to 99.9%, and more preferably from about85 to 99% (particularly, from 90 to 98%). When the total lighttransmittance is too low, transparency may be reduced.

In the present specification and claims, haze and total lighttransmittance can be measured according to JIS K7105 using a haze meter(“NDH-5000W” available from Nippon Denshoku Industries Co., Ltd.).

The 60° gloss (60° gloss of an anti-glare layer surface when theanti-glare film includes a laminate made of the anti-glare layer and atransparent substrate layer) of the anti-glare film of the presentinvention may be 15% or less and, from the perspective of improvingvisibility, from about 0 to 13%, preferably from about 0.1 to 12% (forexample, from 0.2 to 10%), and more preferably from about 0.3 to 5%(particularly, from 0.5 to 1%), for example. A 60° gloss within such arange is effective in display devices with a medium-sized screen andparticularly effective in display devices with a resolution from about50 to 150 ppi. Furthermore, among display devices with a medium-sizedscreen, from the perspective of obtaining a balance between visibility,transparency, and anti-glare properties, a display device with aresolution of greater than about 150 ppi and about 300 ppi or less has a60° gloss of from about 3 to 15%, preferably from about 5 to 12%, andmore preferably from about 6 to 10%, for example. When 60° gloss is toogreat, anti-glare properties may be reduced.

In the present specification and claims, the 60° gloss can be measuredusing a gloss meter (“IG-320” manufactured by Horiba, Ltd.) inaccordance with JIS K8741.

The transmission image clarity of the anti-glare film of the presentinvention, measured using an optical comb with a width of 0.5 mm, may be80% or less (for example, from 1 to 80%), preferably from about 3 to 70%(for example, from 5 to 60%), and more preferably from about 10 to 50%(particularly from 30 to 40%), for example. A transmission image claritywithin such a range is effective in display devices with a medium-sizedscreen and particularly effective in display devices with a resolutionfrom about 50 to 150 ppi. Furthermore, among display devices with amedium-sized screen, from the perspective of obtaining a balance betweenvisibility, transparency, and anti-glare properties, a display devicewith a resolution of greater than about 150 ppi and about 300 ppi orless has a transmission image clarity measured using an optical combwith a width of 0.5 mm of from about 1 to 30%, preferably from about 1.5to 20% (for example, from 2 to 10%), and more preferably from about 3 to7% (particularly, from 4 to 6%), for example. When transmission imageclarity is too great, anti-glare properties may be reduced.

Transmission image clarity is a scale for quantitating blur anddistortion of light transmitted through a film. Transmission imageclarity is obtained by measuring light transmitted through a filmthrough a moving optical comb and calculating the value from the amountof light in the light and dark portions of the optical comb. In otherwords, when light is blurred by a film, the slit image formed on theoptical comb is thicker. Thus, the amount of light in the transmittingportion is 100% or less, and the amount of light in the non-transmittingportion is 0% or greater due to leakage of light. A value C fortransmission image clarity is defined by the following formula from amaximum value M of transmitted light of a transparent portion of theoptical comb and a minimum value m of transmitted light of anon-transparent portion of the optical comb.C(%)=[(M−m)/(M+m)]×100

In other words, values of C closer to 100% mean less blurring of theimage by the anti-glare film (Reference Document: Suga and Mitamura,Coating Technology, July 1985 edition).

An example of a measurement device for measuring the transmission imageclarity includes the ICM-1DP image clarity meter available from SugaTest Instruments Co. Ltd. An optical comb with a width of from 0.125 to2 mm can be used.

Anti-Glare Layer

The anti-glare film of the present invention is required to include ananti-glare layer to achieve the optical properties described above.Other than this, the materials and structure are not limited. However,typically, anti-glare properties can be improved by forming the finerecesses and protrusions in the surface with a transparent material toreduce reflection of outside scenery, which is caused from surfacereflections, by the recesses and protrusions.

The anti-glare film of the present invention may include a singleanti-glare layer or may include a transparent substrate layer and ananti-glare layer formed on at least one surface of the transparentsubstrate layer.

The anti-glare layer is required to be formed of a transparent material.The material may be organic or inorganic material. However, from theperspective of productivity and handling properties, an anti-glare layerformed of a composition including a resin component is preferable. Thesurface of the anti-glare layer typically includes recesses andprotrusions. The recesses and protrusions are not particularly limitedand may be formed by physical processing or transfer using a mold.However, from the perspective of productivity and the like, for theanti-glare layer formed of a composition including a resin component,the fine recesses and protrusions corresponding to the shape of finerecesses and protrusions and particles formed by the phase separatedstructure of the resin component may be adopted. Among these, in a curedproduct of cured composition including at least one type of curableresin precursor component, recesses and protrusions formed throughspinodal decomposition from a liquid phase (liquid phase spinodaldecomposition) or recesses and protrusions formed by the particle shapeof impregnated particles (for example, thermoplastic resin particlessuch as polyamide particles, crosslinked polymer particles such ascrosslinked poly(meth)acrylate particles, crosslinked polystyreneparticles, crosslinked polyurethane particles, and the like) arepreferable and, from the perspective of facilitating formation ofrecesses and protrusions to achieve visibility, transparency, andanti-glare properties in a compatible manner, recesses and protrusionsformed through liquid phase spinodal decomposition is particularlypreferable.

The anti-glare layer including the recesses and protrusions formedthrough liquid phase spinodal decomposition may be a cured product of acurable composition including one or more types of a polymer componentand one or more types of a curable resin precursor component.Specifically, the anti-glare layer may be formed in a phase separatedstructure generally having a regular phase to phase distance by thephase separation, which proceeded through the spinodal decomposition asthe concentration of the mixed liquid increased in the process ofevaporating or removing the solvent from the liquid phase of thecomposition by drying or the like. The composition (mixed liquid) usedincludes one or more types of a polymer component and one or more typesof a curable resin precursor component. Specifically, the liquid phasespinodal decomposition is typically performed by coating a support withthe composition (homogeneous mixed liquid) and vaporizing the solventfrom the applied layer. When a peelable support is used as the support,an anti-glare film formed of only an anti-glare layer can be obtained bypeeling the anti-glare layer from the support. When a transparentnon-peelable support (transparent substrate layer) is used as thesupport, an anti-glare film with a multilayer structure formed of thetransparent substrate layer and the anti-glare layer can be obtained.

Polymer Component

As the polymer component, a thermoplastic resin is typically used. Thethermoplastic resin is not particularly limited as long as it has hightransparency and can form the above-mentioned surface recesses andprotrusions through the spinodal decomposition, but examples of thethermoplastic resin include a styrene-based resin, a (meth)acrylatepolymer, an organic acid vinyl ester polymer, a vinyl ether-basedpolymer, a halogen-containing resin, polyolefin (including alicyclicpolyolefin), polycarbonate, polyester, polyamide, thermoplasticpolyurethane, a polysulfone-based resin (polyether sulfone, polysulfone,and the like), a polyphenylene ether-based resin (polymer of 2,6-xylenoland the like), a cellulose derivative (cellulose esters, cellulosecarbamates, cellulose ethers, and the like), a silicone resin(polydimethylsiloxane, polymethylphenylsiloxane, and the like), andrubber or elastomer (diene rubber such as polybutadiene andpolyisoprene, a styrene-butadiene copolymer, an acrylonitrile-butadienecopolymer, acrylic rubber, urethane rubber, and silicone rubber, and thelike). These thermoplastic resins can be used alone or in combination oftwo or more.

Of the polymer components, styrene-based resins, (meth)acrylic polymers,vinyl acetate-based polymers, vinyl ether-based polymers,halogen-containing resins, alicyclic polyolefins, polycarbonates,polyesters, polyamides, cellulose derivatives, silicone-based resins,rubbers, or elastomers are generally used. Also, the polymer componentis typically non-crystalline, and a polymer component soluble in anorganic solvent (particularly, a common solvent that can dissolve aplurality of polymer components and curable resin precursor components)is used. In particular, polymer components having high moldability orfilm forming properties, transparency, and weather resistance, such asstyrene-based resins, (meth)acrylic polymers, alicyclic polyolefins,polyester-based resins, cellulose derivatives (cellulose esters and thelike) are preferable and (meth)acrylic polymers and cellulose esters areparticularly preferable.

As the (meth)acrylate polymer, a homopolymer or a copolymer of a(meth)acrylate monomer, or a copolymer of a (meth)acrylate monomer and acopolymerizable monomer can be used. Examples of the (meth)acrylatemonomer include: (meth)acrylic acid; C₁₋₁₀ alkyl (meth)acrylate such asmethyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate,t-butyl (meth)acrylate, isobutyl (meth)acrylate, hexyl (meth)acrylate,octyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate; aryl(meth)acrylate such as phenyl (meth)acrylate; hydroxyalkyl(meth)acrylates such as hydroxyethyl (meth)acrylate and hydroxypropyl(meth)acrylate; glycidyl (meth)acrylate; N,N-dialkylaminoalkyl(meth)acrylate; (meth)acrylonitrile; and (meth)acrylate having analicyclic hydrocarbon group such as tricyclodecane. Examples of thecopolymerizable monomer include a styrene monomer such as styrene, avinyl ester-based monomer, maleic anhydride, maleate, and fumarate.These monomers can be used alone or in combination of two or more.

Examples of the (meth)acrylate-based polymer include poly(meth)acrylateester such as polymethylmethacrylate, amethylmethacrylate-(meth)acrylate copolymer, amethylmethacrylate-(meth)acrylate ester copolymer, amethylmethacrylate-acrylate ester-(meth)acrylate copolymer, and a(meth)acrylate ester-styrene copolymer (MS resin and the like). Amongthose, poly C₁₋₆ alkyl(meth)acrylate such as poly methyl(meth)acrylate,and in particular, a methyl methacrylate-based polymer composed ofmethylmethacrylate as a main component (from about 50 to 100 wt. % andpreferably from about 70 to 100 wt. %, for example) is preferred.

Examples of the cellulose esters include aliphatic organic acid ester(cellulose acetates such as cellulose diacetate and cellulosetriacetate; C₁₋₆ aliphatic carboxylic acid ester such as cellulosepropionate, cellulose butyrate, cellulose acetate propionate, andcellulose acetate butyrate, and the like), aromatic organic acid esters(C₇₋₁₂ aromatic carboxylic acid esters such as cellulose phthalate andcellulose benzoate), inorganic acid esters (for example, cellulosephosphate, cellulose sulfate, and the like), and the cellulose estersmay be mixed acid esters such as acetic acid and cellulose nitrateeater. These cellulose esters can be used alone or in combination of twoor more. Among those, cellulose diacetates, cellulose triacetates, andcellulose C₂₋₄ acylates such as cellulose acetate propionates andcellulose acetate butyrates are preferred, and cellulose acetate C₃₋₄acylates such as cellulose acetate propionates are particularlypreferred.

The polymer component (particularly, the (meth)acrylate-based polymer)may be a polymer having a functional group involved in the curingreaction (or a functional group able to react with the curable resinprecursor component). The polymer may have a functional group in themain chain or side chain. The functional group may be introduced intothe main chain by copolymerization or co-condensation, but is usuallyintroduced into the side chain. Examples of the functional group includecondensable groups, reactive groups (for example, a hydroxyl group, anacid anhydride group, a carboxyl group, an amino group or an iminogroup, an epoxy group, a glycidyl group, or an isocyanate group), andpolymerizable groups (for example, C₂₋₆ alkenyl groups such as vinyl,propenyl, isopropenyl, butenyl, and allyl groups, C₂₋₆ alkynyl groupsuch as ethynyl, propynyl, and butynyl groups, C₂₋₆ alkenylidene groupssuch as a vinylidene group, or a group (such as a (meth)acryloyl group)having a polymerizable group thereof). Of these functional groups, apolymerizable group is preferable.

Examples of the method for introducing a polymerizable group into a sidechain include a method in which a thermoplastic resin having afunctional group such as a reactive group and a condensable group isreacted with a polymerizable compound having a group that is reactivewith the functional group.

For the thermoplastic resin having the functional group, examples of thefunctional group include a carboxyl group or an acid anhydride groupthereof, a hydroxyl group, an amino group, and an epoxy group.

When the thermoplastic resin having the functional group is athermoplastic resin having a carboxyl group or an acid anhydride groupthereof, examples of the polymerizable compound having a group reactivewith the functional group described above include a polymerizablecompound having an epoxy group or a hydroxyl group, an amino group, anisocyanate group, and the like. Among those, the polymerizable compoundhaving the epoxy group, for example, epoxycyclo C₅₋₈ alkenyl(meth)acrylate such as epoxycyclohexenyl (meth)acrylate, glycidyl(meth)acrylate, and allylglycidylether, are widely used.

Representative examples include a combination of a thermoplastic resinhaving a carboxyl group or an acid anhydride group thereof and acompound containing an epoxy group, and particularly include acombination of a (meth)acrylate-based polymer((meth)acrylate-(meth)acrylate ester copolymer and the like) and epoxygroup-containing (meth)acrylate (epoxycycloalkenyl (meth)acrylate,glycidyl (meth)acrylate, and the like). Specifically, a polymer in whicha polymerizable unsaturated group is introduced into a part of carboxylgroups of a (meth)acrylate polymer, for example, a (meth)acryliccopolymer (cyclomer-P available from Daicel Corporation) in which apolymerizable group (photopolymerizable unsaturated group) is introducedinto a side chain by reacting an epoxy group of3,4-epoxycyclohexenylmethyl acrylate with a part of carboxyl groups of a(meth)acrylate-(meth)acrylate ester copolymer can be used.

The amount of the functional group (in particular, the polymerizablegroup) involved in the curing reaction for thermoplastic resinintroduced into the thermoplastic resin is, for example, from about0.001 to 10 moles, preferably from about 0.01 to 5 moles, and morepreferably from about 0.02 to 3 moles with respect to 1 kg of thethermoplastic resin.

These polymer components can be used in combination as appropriate. Thatis, the polymer component may be composed of a plurality of polymers.These plurality of polymers may be phase separable through liquid phasespinodal decomposition. Also, the plurality of polymers may be mutuallyimmiscible. When the plurality of polymers are combined, the combinationof a first polymer and a second polymer is not particularly limited, anda plurality of polymers which are mutually immiscible near a processingtemperature, for example, two immiscible polymers, can be appropriatelymixed and used. For example, when the first polymer is a(meth)acrylic-based polymer (for example, polymethyl methacrylate, a(meth)acrylic-based polyer having a polymerizable group, and the like),the second polymer may be a cellulose ester (such as a cellulose acetateC₃₋₄ acylate such as cellulose acetate propionate), a polyester (such asa urethane-modified polyester).

Furthermore, from the perspective of scratch resistance after curing, atleast one of the plurality of polymers, for example, one of the mutuallyimmiscible polymers (at least one of the polymers when the first polymerand the second polymer are combined), is preferably a polymer that has afunctional group (particularly, a polymerizable group) capable ofreacting with the cured resin precursor component in the side chain.

The weight ratio between the first polymer and the second polymer (firstpolymer/second polymer) can set to range from about 1/99 to 99.9/0.1 andpreferably from about 5/95 to 99.5/0.5, for example. In particular, whenthe first polymer is a (meth)acrylic-based polymer and the secondpolymer is a cellulose ester, for a display device with a resolution offrom about 50 to 150 ppi (in particular, a medium-sized screen displaydevice), the weight ratio of the two polymers (first polymer/secondpolymer) is from about 50/50 to 99/1, preferably from about 55/45 to90/10, and more preferably from about 60/40 to 80/20 (in particular,from 65/35 to 75/25), for example, and for a display device with aresolution of greater than about 150 and about 300 ppi or less (inparticular, a medium-sized screen display device), the weight ratio ofthe two polymers is from about 50/50 to 99.5/0.5, preferably from about70/30 to 99/1, and more preferably from about 90/10 to 98.5/1.5 (inparticular, from 95/5 to 98/2), for example.

Note that the polymer for forming the phase separated structure mayinclude a thermoplastic resin or another polymer in addition to the twoimmiscible polymers described above.

A glass transition temperature of the polymer component can be selected,for example, from the range of from about −100° C. to 250° C.,preferably from about −50° C. to 230° C., and more preferably from about0 to 200° C. (for example, from about 50 to 180° C.). From the viewpointof surface hardness, the glass transition temperature is advantageously50° C. or higher (for example, from about 70 to 200° C.), and preferablyfrom 100° C. or higher (for example, from about 100 to 170° C.). Aweight average molecular weight of the polymer component can beselected, for example, from the range of about 1000000 or less andpreferably from about 1000 to 500000.

Curable Resin Precursor Component

The curable resin precursor component is a compound having a functionalgroup that undergoes a reaction by heat, active energy rays (such asultraviolet rays or electron beams) and the like, and various curablecompounds which undergo curing or crosslinking by heat, active energyrays or the like and capable of forming a resin (in particular, cured orcrosslinked resin) can be used. Examples of the curable resin precursorcomponent include a thermosetting compound or a resin (low molecularweight compounds having an epoxy group, a polymerizable group, anisocyanate group, an alkoxysilyl group, a silanol group, and the like(for example, an epoxy resin, an unsaturated polyester resin, a urethaneresin, and a silicone resin)), a photocurable compound which can becured by active rays (such as ultraviolet rays, electron beam (EB), andthe like) (ultraviolet curable compounds, such as photocurable monomerand oligomers, and electron beam curable compounds), and the like. Notethat the photocurable compound such as a photocurable monomer, aphotocurable oligomer, and a photocurable resin that may have a lowmolecular weight may be simply referred to as a “photocurable resin”.

Examples of the photocurable compound include a monomer and an oligomer(or resin, in particular, low molecular weight resin).

Examples of the monomer include monofunctional monomers[(meth)acrylate-based monomers such as (meth)acrylate ester, vinyl-basedmonomers such as vinylpyrrolidone, (meth)acrylate having a bridgedcyclic hydrocarbon group such as isobornyl (meth)acrylate and adamantyl(meth)acrylate], and a ployfunctional monomer having at least twopolymerizable unsaturated bonds [alkylene glycol di(meth)acrylates suchas ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate,butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, andhexanediol di(meth)acrylate; (poly)oxyalkylene glycol di(meth)acrylatessuch as diethylene glycol di(meth)acrylate, dipropylene glycoldi(meth)acrylate, polyoxytetramethylene glycol di(meth)acrylate;di(meth)acrylates having a crosslinking cyclic hydrocarbon group such astricyclodecane dimethanol di(meth)acrylate and adamantanedi(meth)acrylate; and a polyfunctional monomer having about 3 to 6polymerizable unsaturated bonds such as glycerin tri(meth)acrylate,trimethylolpropane tri(meth)acrylate, trimethylolethanetri(meth)acrylate, pentaerythritol tri(meth)acrylate,ditrimethylolpropane tetra(meth)acrylate, pentaerythritoltetra(meth)acrylate, dipentaerythritol penta(meth)acrylate,dipentaerythritol hexa(meth)acrylate], and the like.

Examples of the oligomer or the resin include (meth)acrylate of abisphenol A-alkylene oxide adduct, epoxy (meth)acrylate [bisphenol Atype-epoxy (meth)acrylate, novolac-type epoxy (meth)acrylate, and thelike], polyester (meth)acrylate [for example, aliphatic polyester-type(meth)acrylate, aromatic polyester-type (meth)acrylate, and the like],(poly)urethane (meth)acrylate [polyester-type urethane (meth)acrylate,polyether-type urethane (meth)acrylate, and the like], and silicone(meth)acrylate, and the like.

These photocurable compounds can be used alone or in combination of twoor more. Among those, the photocurable compound that can be cured in ashort time, for example, an ultraviolet curable compound (monomer,oligomer, and resin that may have a low molecular weight), and an EBcurable compound are preferable. In particular, the practicallyadvantageous photocurable compound (resin precursor component) is anultraviolet curable compound. In addition, to improve resistance such asscratch resistance, the photocurable compound is preferably a compoundhaving 2 or more (preferably from 2 to 6 and more preferably from 2 to4, for example) polymerizable unsaturated bonds in the molecule.

A weight average molecular weight of the curable resin precursorcomponent is not particularly limited, but in consideration ofmiscibility with the polymer, the weight average molecular weight maybe, for example, about 5000 or less, preferably about 2000 or less, andmore preferably about 1000 or less, for example.

Depending on the type, the cured resin precursor component may include afiller and/or a fluorine atom and thus improve the transparency and theanti-glare properties of the anti-glare film.

Examples of the filler include inorganic particles such as silicaparticles, titania particles, zirconia particles, and alumina particles,organic particles such as crosslinked (meth)acrylate-based polymerparticles, and crosslinked styrene resin particles. These fillers can beused alone or in combination of two or more.

Among these fillers, nanometer-sized silica particles (silicananoparticles) are preferable from the viewpoint of superior opticalproperties and easily forming recesses and protrusions, through spinodaldecomposition, which provide transparency and anti-glare property in acompatible manner. The silica nanoparticles are preferably solid silicananoparticles from the viewpoint that the yellowness of the anti-glarefilm can be suppressed. In addition, an average particle diameter of thesilica nanoparticles is, for example, from about 1 to 800 nm, preferablyfrom about 3 to 500 nm, and more preferably from about 5 to 300 nm.

The ratio of the filler (in particular, silica nanoparticles) may beabout 10 to 90 wt. %, for example, from about 10 to 80 wt. %, preferablyfrom about 15 to 70 wt. %, and more preferably from about 20 to 50 wt. %with respect to the entire curable resin precursor component.

Examples of the precursor component (fluorine-based compound having afluorine-containing curable compound or polymerizable group) containingthe fluorine atom include fluorides of the monomer and the oligomer, forexample, fluorinated alkyl (meth)acrylate [for example, perfluorooctylethyl (meth)acrylate, trifluoroethyl (meth)acrylate, and the like],fluorinated (poly)oxyalkylene glycol di(meth)acrylate [for example,fluoroethylene glycol di(meth) acrylate, fluoropolyethylene glycoldi(meth)acrylate, fluoropropylene glycol di(meth)acrylate, and thelike], a fluorine-containing epoxy resin, a fluorine-containingurethane-based resin, and the like. Among those, a fluoropolyethercompound having a (meth)acryloyl group is preferred. Thefluorine-containing curable compound may be a commercially availablefluorine-based polymerizable leveling agent.

The curable resin precursor component may further include a curing agentdepending on the type of the curable resin precursor component. Forexample, the thermosetting resin may include a curing agent such asamines and polyvalent carboxylic acids, and the photocurable resin mayinclude a photopolymerization initiator. Examples of thephotopolymerization initiator include the known components such asacetophenones or propiophenones, benzyls, benzoins, benzophenones,thioxanthones, acylphosphine oxides, and the like. The ratio of a curingagent such as the photopolymerization initiator is, for example, fromabout 0.1 to 20 wt. %, preferably from about 0.5 to 10 wt. %, and morepreferably from about 1 to 8 wt. % with respect to the entire curableresin precursor component.

The curable resin precursor component may further include a curingaccelerator. For example, the photocurable resin may include aphotocuring accelerator, for example, a tertiary amines (such as adialkylaminobenzoate), and a phosphine-based photopolymerizationaccelerator.

Of these cured resin precursor components, a polyfunctional(meth)acrylate (for example, a (meth)acrylate having from about 2 to 8polymerizable groups, such as dipentaerythritol hexa (meth)acrylate);epoxy (meth) acrylate, polyester (meth)acrylate, urethane(meth)acrylate, silicone (meth)acrylate, and the like are preferable.Furthermore, the cured resin precursor component preferably includessilica nanoparticles and/or fluorine atoms, and particularly includes asilica nanoparticle-containing photocurable compound (in particular, apolyfunctional (meth)acrylate including silica nanoparticles, a urethane(meth)acrylate including silica nanoparticles, and a silicone(meth)acrylate including silica nanoparticles,) and afluorine-containing curable compound.

Preferred combinations for the curable resin precursor componentinclude, for example, a combination of a silica nanoparticle-containingphotocurable compound and a silicone (meth)acrylate, a combination of aurethane (meth)acrylate, a trifunctional to hexafunctional(meth)acrylate, a silicone (meth)acrylate, and a fluorine-containingcurable compound, and a combination of a silica nanoparticle-containingphotocurable compound and a fluorine-containing curable compound. Aparticularly preferred combination for a display device with aresolution of from about 50 to 150 ppi (in particular, a medium-sizedscreen display device) is a combination of a silicananoparticle-containing photocurable compound and a fluorine-containingcurable compound and for a display device with a resolution of greaterthan about 150 and about 300 ppi or less (in particular, a medium-sizedscreen display device) a combination of urethane (meth)acrylate andsilicone (meth)acrylate.

In the present invention, from the perspective of facilitating formationof recesses and protrusions for obtaining visibility, transparency, andanti-glare properties in a compatible manner, to achieve the proportiondescribed above of silica nanoparticles in the entire curable resinprecursor component, the curable resin precursor component preferablyincludes the silica nanoparticle-containing curable resin precursorcomponent. Also, the proportion of the fluorine-containing curablecompound in the entire curable resin precursor component is, forexample, from about 0.001 to 1 wt. % (for example, from 0.01 to 0.5 wt.%), preferably from 0.02 to 0.3 wt. % (for example, from 0.03 to 0.2 wt.%), and more preferably from 0.05 to 0.1 wt. %.

When the urethane (meth)acrylate and the silicone (meth)acrylate arecombined, the ratio of silicone (meth)acrylate is, for example, fromabout 0.1 to 10 parts by weight, preferably from about 0.3 to 5 parts byweight, and more preferably from about 0.5 to 3 parts by weight (inparticular, from 1 to 2 parts by weight) per 100 parts by weight ofurethane (meth)acrylate.

Combination of Polymer Component and Curable Resin Precursor Component

In the present invention, at least two components of the polymercomponent and the curable resin precursor component are used in acombination in which the at least two components phase separate from oneanother near the processing temperature. Examples of the combinationthat undergo phase separation include (a) a combination in which aplurality of polymer components are immiscible one another and phaseseparate, (b) a combination in which a polymer component and a curableresin precursor component are immiscible and phase separate, and (c) acombination in which a plurality of curable resin precursor componentsare immiscible one another and phase separate. Of these combinations,typically the combination (a) of a plurality of polymer components, andthe combination (b) of a polymer and a curable resin precursor are used,and the combination of (a) a plurality of polymer components ispreferable. If both components to be phase separated have highmiscibility, they do not effectively phase separate in the dryingprocess for vaporizing the solvent, and the function as an anti-glarelayer is decreased.

Note that the polymer component and the curable resin precursorcomponent are typically immiscible. In the case of the polymer componentand the cured resin precursor component being immiscible and phaseseparated, a plurality of polymer components may be used as the polymercomponent. When a plurality of polymer components are used, at least oneof the polymer components is required to be immiscible with the curableresin precursor component. The other polymer components may be misciblewith the curable resin precursor component. Also, a combination of twopolymer components that are immiscible each other and a curable resinprecursor component (in particular, a monomer or oligomer having aplurality of curable functional groups) may be used.

In the case where the polymer component includes a plurality of polymercomponents that are immiscible with one another and phase separates, thecombination includes a curable resin precursor component which ismiscible with at least one polymer component of the plurality ofimmiscible polymer components near the processing temperature. That is,in the case where the plurality of polymer components that areimmiscible with one another include a first polymer and a secondpolymer, for example, the curable resin precursor component is requiredto be miscible with the first polymer or the second polymer, or requiredto be miscible with both polymer components, but is preferably misciblewith only one of the polymer components. In the case where it ismiscible with both polymer components, a mixture including the firstpolymer and the curable resin precursor component as main components anda mixture of the second polymer and the curable resin precursorcomponent as main components phase separate into at least a dual phase.

If the selected plurality of polymer components have high miscibility,the polymer components do not effectively phase separate with oneanother in the drying process for vaporizing the solvent, and thefunction as an anti-glare layer is decreased. The phase separationcapability of the plurality of polymer components can be simplydetermined by preparing a homogeneous solution of the polymer componentsby using a good solvent for the each component, and by visuallyobserving whether a residual solid becomes cloudy during the process ofgradual vaporization of the solvent.

Also, the refractive index of the polymer component and the refractiveindex of the cured resin or crosslinked resin produced by curing thecurable resin precursor mutually differ. Moreover, the refractiveindexes of the plurality of polymer components (the first polymer andthe second polymer) also mutually differ. The difference in refractiveindex between the polymer component and the cured or crosslinked resin,and the difference in refractive index between the plurality of polymercomponents (the first polymer and the second polymer) may be, forexample, from about 0.001 to 0.2, and preferably from about 0.05 to0.15.

The ratio (weight ratio) between the polymer component and the curableresin precursor component is not particularly limited, and can beselected, for example, (polymer component/curable resin precursorcomponent) from the range of from about 1/99 to 95/5, for example fromabout 2/98 to 90/10, preferably from about 3/97 to 80/20, and morepreferably from about 5/95 to 70/30. Also, for a display device with aresolution of from about 50 to 150 ppi (in particular, a medium-sizedscreen display device), the ratio may be, for example, from about 2/98to 30/70, preferably from about 3/97 to 20/80, and more preferably fromabout 5/95 to 15/85. Furthermore, for a display device with a resolutionof greater than about 150 and about 300 ppi or less (in particular, amedium-sized screen display device), the ratio may be, for example, fromabout 10/90 to 60/40, preferably from about 20/80 to 50/50, and morepreferably from about 35/65 to 45/55.

Other Components

The anti-glare layer formed from a composition including a resincomponent may also contain various additives, such as leveling agents,stabilizers (antioxidants, ultraviolet absorbing agents, etc.),surfactants, water-soluble polymers, fillers, cross-linking agents,coupling agents, coloring agents, flame retardants, lubricants, waxes,preservatives, viscosity modifiers, thickening agents, or antifoamingagents. The total proportion of the additives to the entire anti-glarelayer is, for example, from about 0.01 to 10 wt. % (in particular, from0.1 to 5 wt. %).

Thickness of Anti-Glare Layer

The thickness (average thickness) of the anti-glare layer may be, forexample, from about 0.3 to 20 μm, preferably from about 1 to 15 μm (forexample, from 1 to 10 μm), and is typically from about 3 to 12 μm(particularly, from 4 to 10 μm). Note that in the case where theanti-glare film is constituted by the anti-glare layer only, thethickness (average thickness) of the anti-glare layer is, for example,from about 1 to 100 μm, and preferably from about 3 to 50 μm.

Transparent Substrate Layer

The transparent substrate layer is required to be made of a transparentmaterial. The transparent material can be selected according to use andmay be an inorganic material such as glass, but an organic material iswidely used from the viewpoint of strength and moldability. Examples ofthe organic material include a cellulose derivative, polyester,polyamide, polyimide, polycarbonate, and a (meth)acrylic-based polymer.Among those, the cellulose ester, the polyester, and the like are widelyused.

Examples of the cellulose ester include cellulose acetate such ascellulose triacetate (TAC), and cellulose acetate C₃₋₄ acylate such ascellulose acetate propionate and cellulose acetate butyrate. Examples ofthe polyester include polyalkylenearylates such as polyethyleneterephthalate (PET) and polyethylene naphthalate (PEN).

Among those, poly C₂₋₄ alkylenearylates such as PET and PEN arepreferred from the perspective of having an excellent balance inmechanical properties, transparency, or the like.

The transparent substrate layer may also include a commonly usedadditive given as an example in the section on the anti-glare layer. Theproportion of the additive is the same as for the anti-glare layer.

The transparent substrate layer may be a uniaxially or biaxiallystretched film, but may also be an unstretched film from the perspectiveof having a low birefringence and excellent optically isotropicproperties.

The transparent substrate layer may be subjected to surface treatment(for example, corona discharge treatment, flame treatment, plasmatreatment, ozone or ultraviolet irradiation treatment, or the like), andmay include an easily adhesive layer.

The thickness (average thickness) of the transparent substrate layer is,for example, from about 5 to 2000 μm, preferably from about 15 to 1000μm, and more preferably from about 20 to 500 μm.

Adhesive Layer

The anti-glare film of the present invention can also be used as aprotective film on a touch panel display device such as a smart phoneand a PC (tablet PC and the like). In these applications, the adhesivelayer may be formed on at least a portion of the other surface of thetransparent substrate layer.

The adhesive layer is formed of a typical transparent adhesive. Examplesof the adhesive include rubber-based adhesives, acrylic-based adhesives,olefin-based adhesives (such as modified olefin adhesives), andsilicone-based adhesives. Among these adhesives, silicone-basedadhesives are preferable from the perspective of optical properties,reworkability, or the like.

The thickness (average thickness) of the adhesive layer is, for example,from about 1 to 150 μm, preferably from about 10 to 100 μm, morepreferably from about 20 to 70 μm (particularly from 25 to 50 μm).

The adhesive layer may be formed on the entire surface of the othersurface, or may be formed on a portion (for example, a peripheralportion) of the other surface. Further, in a case where the adhesivelayer is formed on the peripheral portion, in order to improve thehandling during adhering, the adhesive layer can be formed on aframe-like member which is formed on the peripheral portion of theanti-glare film (for example, a plastic sheet layered on the peripheralportion).

Method for Producing Anti-Glare Film

The method for producing the anti-glare film of the present invention isnot particularly limited and can be appropriately selected according tothe type of material. The method may include forming by transfer using aphysical process or mold, and from the perspective of productivity andthe like, the method preferably includes curing a curable composition byheat or an active energy ray. Specifically, the anti-glare film,including the anti-glare layer including the recesses and protrusionsformed through liquid phase spinodal decomposition, may be produced bythe steps of applying the curable composition including at least onetype of polymer component and at least one type of curable resinprecursor component to the support (in particular, the transparentsubstrate layer) and drying the obtained body, phase separating throughliquid phase spinodal decomposition the at least two components selectedfrom the polymer component and the curable resin precursor component,then curing the phase separated curable composition by heat or an activeenergy ray.

In the phase-separating, the curable composition may include a solvent.The solvent can be selected according to the type and solubility of thepolymer component and the curable resin precursor component, and may beat least a solvent which can uniformly dissolve a solid content (forexample, a plurality of polymer components and a curable resin precursorcomponent, a reaction initiator, and other additives). In particular,the phase separated structure may be controlled by adjusting thesolubility of the solvent with regard to the polymer component and thecurable resin precursor. Examples of such solvents include ketones(acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone,and the like), ethers (dioxane, tetrahydrofuran, and the like),aliphatic hydrocarbons (hexane and the like), alicyclic hydrocarbons(cyclohexane and the like), aromatic hydrocarbons (toluene, xylene, andthe like), halogenated carbons (dichloromethane, dichloroethane, and thelike), esters (methyl acetate, ethyl acetate, butyl acetate, and thelike), water, alcohols (ethanol, isopropanol, butanol, cyclohexanol, andthe like), cellosolves [methyl cellosolve, ethyl cellosolve, propyleneglycol monomethyl ether (1-methoxy-2-propanol), and the like],cellosolve acetates, sulfoxides (dimethyl sulfoxide and the like), andamides (dimethylformamide, dimethylacetamide, and the like). Inaddition, the solvent may be a mixed solvent.

Among these solvents, ketones such as methyl ethyl ketone arepreferable, and a mixed solvent of ketones with alcohols (butanol andthe like) and/or cellosolves (1-methoxy-2-propanol and the like) isparticularly preferable. In the mixed solvent, the ratio of alcoholsand/or cellosolves (total amount in the case of both being mixed)relative to 100 parts by weight of ketones for a display device with aresolution of from about 50 to 150 ppi (in particular, a medium-sizedscreen display device) is from about 10 to 150 parts by weight,preferably from about 15 to 100 parts by weight, and more preferablyfrom about 20 to 80 parts by weight (in particular, from 25 to 50 partsby weight) and for a display device with a resolution of greater thanabout 150 and about 300 ppi or less (in particular, a medium-sizedscreen display device) is from about 3 to 100 parts by weight,preferably from about 5 to 50 parts by weight, and more preferably fromabout 10 to 30 parts by weight (in particular from 15 to 20 parts byweight), for example. In the case where the combination includingalcohols and cellosolves, the ratio of the cellosolves per 100 parts byweight of the alcohols is from about 10 to 120 parts by weight,preferably from about 30 to 100 parts by weight, and more preferablyfrom about 50 to 80 parts by weight (in particular, from 60 to 70 partsby weight). In an embodiment of the present invention, the phaseseparation can be adjusted by the spinodal decomposition by theappropriate combination with the solvent to form the recesses andprotrusions that can provide visibility, transparency, and anti-glareproperties in a compatible manner.

The concentration of a solute (polymer component, curable resinprecursor component, reaction initiator, and other additives) in themixed solution can be selected within the range in which the phaseseparation occurs and within the range in which casting properties andcoating properties are not impaired, and is, for example, from about 1to 80 wt. %, preferably from about 10 to 70 wt. %, and more preferablyfrom about 20 to 60 wt. % (in particular, 30 to 55 wt. %).

Examples of the applying method include the known methods such as a rollcoater, an air knife coater, a blade coater, a rod coater, a reversecoater, a bar coater, a comma coater, a dip squeeze coater, a diecoater, a gravure coater, a micro gravure coater, a silk screen coatermethod, a dip method, a spray method, and a spinner method. Among thesemethods, the bar coater method or the gravure coater method are widelyused. If necessary, the applying solution may be applied a plurality oftimes.

After the mixed solution is casted or applied, the phase separation bythe spinodal decomposition can be induced by evaporating the solvent ata temperature lower than a boiling point of the solvent (for example,temperature that is from about 1 to 120° C., preferably from about 5 to50° C., and particularly preferably from about 10 to 50° C. lower thanthe boiling point of the solvent). The solvent can be evaporated bybeing usually dried at a temperature of, for example, from about 30 to200° C. (for example, from 30 to 100° C.), preferably from about 40 to120° C., and more preferably from about 50 to 90° C. (in particular,from 60 to 85° C.) depending on the boiling point of the solvent.

Regularity or periodicity can be imparted to an average distance betweenthe domains of the phase separated structure through such spinodaldecomposition accompanied by the evaporation of the solvent.

In the curing, the dried curable composition is finally cured by activerays (ultraviolet rays, electron beams, and the like) or heat, so thephase separated structure formed through the spinodal decomposition canbe promptly fixed. The curable composition may be cured by a combinationof heating, light irradiation, and the like according to the type of thecurable resin precursor component.

The heating temperature can be selected from an appropriate range, forexample, from about 50 to 150° C. The light irradiation can be selectedaccording to the type of the photocuring component or the like, andusually, ultraviolet rays, electron beams, and the like can be used. Agenerally used light source is typically an ultraviolet irradiationdevice.

Examples of the light source include a deep UV lamp, a low-pressuremercury lamp, a high-pressure mercury lamp, an ultrahigh-pressuremercury lamp, a halogen lamp, and a laser light source (light sourcesuch as a helium-cadmium laser and an excimer laser) in the case of theultraviolet rays. The amount of irradiation light (irradiation energy)varies depending on the thickness of the coating film, and is, forexample, from about 10 to 10000 mJ/cm², preferably from about 20 to 5000mJ/cm², and more preferably from about 30 to 3000 mJ/cm². If necessary,the light irradiation may be performed in an inert gas atmosphere.

Display Device

The anti-glare film of the present invention can achieve transparencyand anti-glare properties in a compatible manner. Thus, it can be usedas an optical member of a display device with a liquid crystal display(LCD), an organic EL display, or a touch panel and is particularlyadvantageous used as an optical element of an LCD or an organic ELdisplay.

In particular, the LCD may be a reflective LCD that utilizes externallight to illuminate a display unit including liquid crystal cells or maybe a transmissive LCD with a backlight unit configured to illuminate thedisplay unit. In a reflective LCD, incident light is introduced from theexterior through the display unit, and transmitted light transmittedthrough the display unit is reflected by a reflective member toilluminate the display unit. In a reflective LCD, the anti-glare film ofthe present invention can be disposed forward in an optical path fromthe reflective member. For example, the anti-glare film of the presentinvention can be disposed at or layered on the front surface (visualviewing side front surface) of the display unit, and in particular, maybe disposed at the front surface of an LCD with a collimated backlightunit and without a prism sheet.

In a transmissive LCD, the backlight unit may include a light guideplate (for example, a light guide plate having a wedge-shaped crosssection) for allowing a light from a light source (a tubular lightsource such as a cold-cathode tube, a point light source such as a lightemitting diode, or the like) incident from one side to emit from thefront output surface. Also, as necessary, a prism sheet may be disposedat the front surface side of the light guide plate. Note that,typically, on the back surface of the light guide plate, a reflectivemember for reflecting light from a light source toward the outputsurface is disposed. In such a transmissive LCD, typically, theanti-glare film of the present invention can be disposed forward in anoptical path from the light source. For example, the anti-glare film ofthe present invention can be disposed at or layered in between a lightguide plate and a display unit, disposed at or layered on a frontsurface of a display unit, or the like.

In an organic EL display, an organic EL includes a light emittingelement constituted for each pixel, and this light emitting element istypically formed of a negative electrode of a metal or the like/anelectron-injecting layer/an electron-transporting layer/a light emittinglayer/a hole-transporting layer/a hole-injecting layer/a positiveelectrode of indium tin oxide (ITO) or the like/a substrate such as aglass plate or a transparent plastic plate. Also, in an organic ELdisplay, the anti-glare film of the present invention may be disposed inan optical path.

Also, the anti-glare film of the present invention may be used as anaftermarket protective film for preventing damage to an LCD (includingan LCD which is a display device with a touch panel) or an organic ELdisplay (including an organic EL display which is a display device witha touch panel).

EXAMPLE(S)

Hereinafter, the present invention is described in greater detail basedon examples, but the present invention is not limited to these examples.The raw materials used in Examples and Comparative Examples are asfollows, and the anti-glare film obtained was evaluated by the followingmethod.

Raw Material

Acrylic-based polymer having a polymerizable group: “Cyclomer P”,available from Daicel-Allnex Ltd.

Cellulose acetate propionate: “CAP-482-20”, available from EastmanChemical Company, degree of acetylation=2.5%, degree ofpropionylation=46%, number average molecular weight calibrated withpolystyrene is 75000

Silicone acrylate: “EB1360”, available from Daicel-Allnex Ltd.

Silicone based hard coat material: “AS-201S” available from TOKUSHIKICo. Ltd.

Urethane acrylate A: “U-15HA” available from Shin-Nakamura Chemical Co.,Ltd.

Urethane acrylate B: “AU-230” available from TOKUSHIKI Co. Ltd.

Dipentaerythritol hexaacrylate: “DPHA”, available from Daicel-AllnexLtd.

Nanosilica-containing acrylic-based UV curable compound: “XR39-C6210”available from Momentive Performance Materials Japan LLC.

Silica-containing acrylic-based ultraviolet curable compound:“Z-757-4RL” available from Aica Kogyo Company, Limited

Acrylic-based ultraviolet curable compound: “Z-757-4CL” available fromAica Kogyo Company, Limited

PMMA Beads A: “SSX-115”, available from Sekisui Chemical Co., Ltd.

PMMA Beads B: “SSX-105”, available from Sekisui Chemical Co., Ltd.

Cross-linked styrene beads: “SX-130H” available from Soken Chemical &Engineering Co., Ltd.

Fluorine-based compound having polymerizable group: “Ftergent 602A”available from Neos Company Limited

Photoinitiator A: “Irgacure 184” available from BASF Japan Ltd.

Photoinitiator B: “Irgacure 907” available from BASF Japan Ltd.

Polyethylene terephthalate (PET) film: “DIAFOIL” available fromMitsubishi Plastics, Inc.

Cellulose triacetate (TAC) film: “FUJITAC TG60UL” available fromFUJIFILM Corporation.

Thickness of Coat Layer

Using an optical film thickness gauge, ten arbitrary points weremeasured, and an average value was calculated.

Light Reflectance

A spectrophotometer (“U-3900H” available from Hitachi High-Tech ScienceCorporation) was used in accordance with JIS Z8701 to performmeasurement. The anti-glare film to be measured was attached to acommercially available black acrylic sheet by an optical adhesive tominimize the influence from reflections from the back surface as much aspossible.

Haze

Haze was measured in accordance with JIS K7136 using a haze meter(“NDH-5000W” available from Nippon Denshoku Industries Co., Ltd.), withthe front surface including the recesses and protrusions structure beingdisposed facing the light receiver.

60° Gloss

Measurement was performed at an angle of 60° using a gloss meter(“IG-320” available from Horiba, Ltd.) in accordance with JIS K7105.

Transmission Image Clarity

Measurement of the image clarity of the anti-glare film was performedusing an image clarity meter (“ICM-1T” available from Suga TestInstruments Co., Ltd.) based on JIS K7105 under a condition in which thefilm is disposed with the film-forming direction and the comb toothdirection of the optical comb being parallel with each other. The imageclarity using a 0.5 mm-width optical comb of the image clarity meter wasmeasured.

Anti-Glare Properties

The prepared anti-glare film was attached to a commercially availableblack acrylic plate by an optical adhesive, and the reflection imagewhen illuminated by a three-wavelength fluorescent lamp was visuallychecked and evaluated according to the following criteria.

Excellent: Shape of fluorescent light not visible

Good: Outline of fluorescent light is faintly visible

Marginal: Outline of fluorescent light can be perceived

Reflectance

The prepared anti-glare film was attached to a commercially availableblack acrylic plate by an optical adhesive, and the intensity of thereflected light when illuminated by a three-wavelength fluorescent lampwas visually checked and evaluated according to the following criteria.

Excellent: Reflective light is almost not visible

Good: Reflective light is slightly visible

Marginal: Reflected light is clearly visible

Character Blur 1

The prepared anti-glare film was attached to a liquid crystal monitor(“P222va” available from Hewlett Packard, resolution: 102 ppi) by anoptical adhesive, and the blur when displaying characters was visuallychecked and evaluated according to the following criteria.

Excellent: Almost no change before and after the anti-glare film isattached

Good: Slight character blur, but no impact on reading

Marginal: Clear character blur, difficult to read but readable

Poor: Significant blur, almost unrecognizable

Character Blur 2

The prepared anti-glare film was attached to a liquid crystal tablet(“iPad Air (trade name)” available from Apple Inc., resolution: 264 ppi)by an optical adhesive, and the blur when displaying characters wasvisually checked and evaluated according to the following criteria.

Excellent: Almost no change before and after the anti-glare film isattached

Good: Slight character blur, but no impact on reading

Marginal: Clear character blur, difficult to read but readable

Poor: Significant blur, almost unrecognizable

Example 1

A solution was prepared by dissolving 15.0 parts by weight of theacrylic-based polymer A having a polymerizable group, 3 parts by weightof the cellulose acetate propionate, 150 parts by weight of thenanosilica-containing acrylic UV curable compound, and 1 part by weightof the silicone acrylate in a mixed solvent of 101 parts by weight ofmethyl ethyl ketone and 24 parts by weight of 1-butanol.

This solution was casted onto a PET film using a wire bar (#20), andthen left in an oven at 80° C. for 1 minute to evaporate the solvent,and a coating layer having a thickness of about 9 μm was formed.

Then, the coat layer was ultraviolet light cured by being irradiatedwith ultraviolet rays by a high-pressure mercury lamp for about 5seconds (irradiation by integrated light amount of about 100 mJ/cm²,same for below) to obtain the anti-glare film.

Example 2

A solution was prepared by dissolving 12.5 parts by weight of theacrylic-based polymer having a polymerizable group, 4 parts by weight ofthe cellulose acetate propionate, 150 parts by weight of thenanosilica-containing acrylic UV curable compound, and 1 part by weightof the silicone acrylate in a mixed solvent of 81 parts by weight ofmethyl ethyl ketone, 24 parts by weight of 1-butanol, and 13 parts byweight of 1-methoxy-2-propanol.

This solution was casted onto a PET film using a wire bar (#20), andthen left in an oven at 80° C. for 1 minute to evaporate the solvent,and a coating layer having a thickness of about 9 μm was formed.

Then, the coat layer was ultraviolet light cured by being irradiatedwith ultraviolet rays by a high-pressure mercury lamp for about 5seconds to obtain the anti-glare film.

Example 3

A solution was prepared by dissolving 45.6 parts by weight of theacrylic-based polymer having a polymerizable group, 2.3 parts by weightof the cellulose acetate propionate, 70.7 parts by weight of theurethane acrylate A, 8.2 parts by weight of the dipentaerythritolhexaacrylate, 0.6 part by weight of the silicone acrylate, 0.1 parts byweight of fluorine-based compound having a polymerizable group, 1 partby weight of the photoinitiator A, and 1 part by weight of thephotoinitiator B in a mixed solvent of 128 parts by weight of methylethyl ketone, 25 parts by weight of 1-butanol, and 31 parts by weight ofcyclohexanone.

This solution was casted onto a TAC film using a wire bar (#16), andthen left in an oven at 80° C. for 1 minute to evaporate the solvent,and a coating layer having a thickness of about 7 μm was formed.

Then, the coat layer was ultraviolet light cured by being irradiatedwith ultraviolet rays by a high-pressure mercury lamp for about 5seconds to obtain the anti-glare film.

Example 4

A solution was prepared by dissolving 12.5 parts by weight of theacrylic-based polymer having a polymerizable group, 5.5 parts by weightof the cellulose acetate propionate, 149 parts by weight of thenanosilica-containing acrylic UV curable compound, and 0.1 parts byweight of fluorine-based compound having a polymerizable group in amixed solvent of 129 parts by weight of methyl ethyl ketone, 24 parts byweight of 1-butanol, and 13 parts by weight of 1-methoxy-2-propanol.

This solution was casted onto a PET film using a wire bar (#14), andthen left in an oven at 80° C. for 1 minute to evaporate the solvent,and a coating layer having a thickness of about 5 μm was formed.

Then, the coat layer was ultraviolet light cured by being irradiatedwith ultraviolet rays by a high-pressure mercury lamp for about 5seconds to obtain the anti-glare film.

Example 5

A solution was prepared by dissolving 7.5 parts by weight of theacrylic-based polymer having a polymerizable group, 5.5 parts by weightof the cellulose acetate propionate, 151.5 parts by weight of thenanosilica-containing acrylic UV curable compound, and 1 part by weightof the silicone acrylate in a mixed solvent of 129 parts by weight ofmethyl ethyl ketone, 24 parts by weight of 1-butanol, and 15 parts byweight of 1-methoxy-2-propanol.

This solution was casted onto a PET film using a wire bar (#14), andthen left in an oven at 80° C. for 1 minute to evaporate the solvent,and a coating layer having a thickness of about 5 μm was formed.

Then, the coat layer was ultraviolet light cured by being irradiatedwith ultraviolet rays by a high-pressure mercury lamp for about 5seconds to obtain the anti-glare film.

Example 6

A solution was prepared by dissolving 50 parts by weight of theacrylic-based polymer having a polymerizable group, 4 parts by weight ofthe cellulose acetate propionate, 76 parts by weight of the urethaneacrylate A, 1 part by weight of the silicone acrylate, 1 part by weightof the photoinitiator A, and 1 part by weight of the photoinitiator B ina mixed solvent of 176 parts by weight of methyl ethyl ketone and 28parts by weight of 1-butanol.

This solution was casted onto a TAC film using a wire bar (#18), andthen left in an oven at 80° C. for 1 minute to evaporate the solvent,and a coating layer having a thickness of about 8 μm was formed.

Then, the coat layer was ultraviolet light cured by being irradiatedwith ultraviolet rays by a high-pressure mercury lamp for about 5seconds to obtain the anti-glare film.

Example 7

A solution was prepared by dissolving 3 parts by weight of the celluloseacetate propionate, 97 parts by weight of the urethane acrylate A, 90parts by weight of the PMMA Beads B, 1 part by weight of thephotoinitiator A, and 1 part by weight of the photoinitiator B in amixed solvent of 277 parts by weight of methyl ethyl ketone and 23 partsby weight of 1-butanol.

This solution was casted onto a PET film using a wire bar (#6), and thenleft in an oven at 80° C. for 1 minute to evaporate the solvent, and acoating layer having a thickness of about 1 μm was formed.

Then, the coat layer was ultraviolet light cured by being irradiatedwith ultraviolet rays by a high-pressure mercury lamp for about 5seconds to obtain the anti-glare film.

Reference Example 1

A solution was prepared by dissolving 39 parts by weight of a urethaneacrylate B, 15.7 parts by weight of a silicon-based hard coat material,0.3 parts by weight of PMMA Beads A, and 6.1 parts by weight ofcrosslinked styrene beads in 38 parts by weight of methyl ethyl ketone.

This solution was casted onto a PET film using a wire bar (#14), andthen left in an oven at 100° C. for 1 minute to evaporate the solvent,and a coating layer having a thickness of about 6 μm was formed.

Then, the coat layer was ultraviolet light cured by being irradiatedwith ultraviolet rays by a high-pressure mercury lamp for about 5seconds to obtain the anti-glare film.

Reference Example 2

A solution was prepared by mixing 50 parts by mass of thesilica-containing acrylic-based ultraviolet curable compound and 150parts by mass of the acrylic-based ultraviolet curable compound. Thissolution was casted onto a PET film using a wire bar (#14), and thenleft in an oven at 80° C. for 1 minute to evaporate the solvent, and acoating layer having a thickness of about 7 μm was formed.

Then, ultraviolet light curing was performed by irradiation withultraviolet rays by an ultraviolet lamp for about 5 seconds to obtainthe anti-glare film.

Table 1 shows the evaluation results of the obtained anti-glare filmsaccording to the Examples and the Reference Examples.

TABLE 1 Example Reference example Items 1 2 3 4 5 6 7 1 2 Haze (%) 68 8076 95 85 44 92 83 3 Light reflectance 3.44 3.46 3.78 2.49 2.50 3.75 3.094.32 4.72 (%) 60° gloss (%) 8 4 5 0.6 6.3 8 0.9 12 90 Transmission 25 812 35 70 5 30 9 70 Image Clarity (%) Anti-glare Good Excellent ExcellentExcellent Good Good Good Good Marginal properties Reflectance Good GoodGood Excellent Excellent Good Good Marginal Marginal Character blur 1Excellent Good Good Good Good Excellent Good Marginal ExcellentCharacter blur 2 Good Marginal Marginal Poor Marginal Excellent PoorPoor Excellent

As can be seen from the results shown in Table 1, the anti-glare film ofthe Examples had high anti-glare properties, suppressed reflectance, andexcellent visibility.

INDUSTRIAL APPLICABILITY

The anti-glare film of the present invention can be used as ananti-glare film that is used in various display devices, such as LCDs,cathode tube display devices, organic or inorganic EL displays, fieldemission displays (FEDs), surface-conduction electron-emitter displays(SEDs), rear projection television displays, plasma displays, anddisplay devices with a touch panel.

In addition, the anti-glare film of the present invention is applicableto screens of various sizes and can be used in display devices withsmall-sized and mobile-sized screen (for example, display devices with adisplay and/or touch panel including car navigation displays, gameconsoles, smart phones, and tablet PCs and the like), display deviceswith a medium-sized screen (for example, PCs including notebook type PCsor laptop type PCs, and desktop type PCs, televisions, and the like),and display devices with a large-sized screen (for example, digitalsignage and the like). The display device can be appropriately selecteddepending on the difference in resolution, but from the perspective ofachieving visibility and anti-glare properties in a compatible manner,the anti-glare film is advantageously used in a display device with amedium-sized screen. Furthermore, of display devices with a medium-sizedscreen, the anti-glare film is particularly advantageously used indisplay devices with a resolution from about 50 to 150 ppi (laptop type,desktop type PCs, televisions, and the like) and display devices with aresolution of greater than about 150 and about 300 ppi or less (notebooktype PCs, tablet PCs, and the like).

Also, the film including the anti-glare layer containing the curableresin precursor component has superior scratch resistance. Thus, it canbe used as an aftermarket protective film for LCDs and organic ELdisplays.

The invention claimed is:
 1. A display device comprising an anti-glarefilm, wherein the display device is a display device with a medium-sizedscreen or a large-sized screen, wherein the display device is a displaydevice with a resolution of greater than 150 ppi and 300 ppi or less,wherein the anti-glare film has a light reflectance of 3.5% or less, ahaze of 50 to 70%, a 60° gloss of 12% or less, and a transmission imageclarity of 8% to 50%, measured using an optical comb with a width of 0.5mm, wherein the anti-glare film comprises: a transparent substratelayer, and an anti-glare layer formed on at least one surface of thetransparent substrate layer, wherein the anti-glare layer is formed of aresin composition comprising a resin component and/or particles, andwherein the surface of the anti-glare layer includes recesses andprotrusions formed by the phase separated structure of the resincomposition, or recesses and protrusions corresponding to the shape ofrecesses and protrusions of the particles.
 2. The display deviceaccording to claim 1, wherein the anti-glare layer is a cured product ofa curable composition comprising one or more polymer components and oneor more curable resin precursor components.
 3. The display deviceaccording to claim 2, wherein at least two components selected from thepolymer component and the curable resin precursor component are able tobe phase separated through liquid phase spinodal decomposition.
 4. Thedisplay device according to claim 2, wherein the polymer componentcomprises a (meth)acrylic-based polymer optionally having a celluloseester and/or a polymerizable group.
 5. The display device according toclaim 2, wherein the curable resin precursor component comprises atleast one selected from a polyfunctional (meth)acrylate, epoxy(meth)acrylate, polyester (meth)acrylate, urethane (meth)acrylate, andsilicone (meth)acrylate.
 6. The display device according to claim 2,wherein the curable resin precursor component comprises a silicananoparticle and/or a fluorine atom.
 7. The display device according toclaim 1, wherein the display device is an organic EL display or a liquidcrystal display.